Starters are known in which, during the starting process, an engaging pinion of the starter motor engages with a toothed wheel of a vehicle drive, particularly of an internal combustion engine.
In the ideal case, the engaging pinion of the starter motor and a corresponding toothed wheel are situated in the vehicle drive rotated with respect to each other such that the engaging pinion glides directly into the toothed wheel. It is also possible, however, that during the engagement process, one tooth of the pinion first overlaps wholly or partially with a tooth of the toothed wheel, and direct engaging is prevented thereby. In the case of a worn pinion, in particular, or a worn toothed wheel, what may happen in such a situation is that the starter motor begins to turn and the engaging pinion does not engage in the toothed wheel because of the tooth position. Or rather, the teeth of the engaging pinion and the teeth of the toothed wheel glide away over one another, so that the vehicle drive is not driven by the starter motor.
In the usual starter motors, it is checked accordingly, for example, whether an engagement process has been completed after a certain time. After this certain time, if no successful engagement process is able to be detected, the engagement process is broken off, for example, and started over again. The effect of this may, however, turn out unfavorably on the operation of starter motors in start-stop systems, in which a new start of the vehicle drive is supposed to take place in as short a time as possible.